Conventionally, there has been known a device for conveying absorbent articles such as disposable diapers and sanitary napkins.
The conveying device of this type is configured to be switchable between a state where absorbent articles are conveyed along a main conveyance path set in advance and a state where the absorbent articles are conveyed along a branch conveyance path branched off from the main conveyance path.
For example, a sorting device described in Japanese Unexamined Patent Publication No. 2012-75627 includes an upstream conveying mechanism for conveying an absorbent article, a downstream conveying mechanism provided downstream of the upstream conveying mechanism on the main conveyance path and a sorting mechanism for guiding the absorbent article to the branch conveyance path in the process of transferring the absorbent article from the upstream conveying mechanism to the downstream conveying mechanism.
The sorting mechanism includes a sorting member formed to intersect with a main conveyance path in a state rotated within a predetermined rotation range about an axis of rotation parallel to the main conveyance path and escape from the main conveyance path in a state rotated within a rotation range other than the former rotation range, and a rotating device for rotating the sorting member.
In the case of guiding the absorbent article to the branch conveyance path in this sorting device, the sorting member starts rotating to intersect with the main conveyance path and rotates to have a speed substantially equal to a conveying speed of the absorbent article with the sorting member and the absorbent article held in contact.
Here, an angular speed of the sorting member rotating about the axis of rotation differs according to a distance (radius) from the axis of rotation.
Thus, a speed difference is created between the absorbent article and the sorting member with the sorting member and the absorbent article held in contact.
In addition, since the rotation and stop of the sorting member are repeated according to whether or not sorting is necessary in the sorting mechanism, it is difficult to suddenly accelerate the sorting member from a stopped state in accordance with the speed of the absorbent article. Also in this respect, a speed difference may be created between the absorbent article and the sorting member.
Since the absorbent article is subject to friction resistance with the sorting member or the upstream conveying mechanism according to the aforementioned speed difference, this frictional resistance acts as a braking force and it may not be possible to precisely sort the absorbent article.